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C.2 Communities and Ecosystems - Coggle Diagram
C.2 Communities and Ecosystems
Food Web
Food webs consists of many interlinked food chains
Therefore organisms exist in multiple food chains often at different trophic levels
Organisms exists within food webs
When stating an organisms trophic level, it needs to be done so relative to a particular food chain
Gersmehl Diagram
: Developed in 1976 to show the difference in nutrient flow and storage between different ecosystems
Sinks for nutrient storage:
Litter
Decomposition
Decomposition of the litter into inorganic nutrients stored by soil
Soil
Plant uptake
Nutrient uptake by plants
Biomass
Littering
Withering, defoliation, excretion, dead bodies, etc
Nutrient gains and loss
Nutrient loss:
Soil: lost through leaching
Litter: lost through surface runoff
Nutrient gain:
Litter: dissolved in raindrops
Soil: gained from weathered rock
Biomass
Littering
Litter
Decomposition
Soil
Plant uptake
Comparisons
: Between biomes the circles (storage) and arrows (gain/loss) increase and decrease in size
Desert
Soil is the main store
Slow rate of nutrient transfer between stores (expect from biomass to litter) because of dry conditions
Tropical rainforest
Biomass is the main store (soil is nutrient poor
Fast rate of nutrient transfer between stores because of warm and wet conditions
Taiga
Litter (pine needles) is the main store
Slow rate of nutrient transfer between stores because of cold temperatures
Gross Production vs. Net Production
Gross production
: Total amount of energy trapped in organic matter produced by plants in an ecosystem
Net production
: GP - energy loss through respiration (NP=GP-R)
Food Conversion Ratio
Farmers measure FCR. It is a measure of an animal's efficiency in converting feed mass into the desired output.
FCR= Mass of food eaten / (increase in) desired output
Low FCR is obtained by minimizing losses of energy through respiration. (Restricting movement, slaughtering at early age, optimizing feed)
Biomes
: Geographical area that has a particular climate and sustains a specific community of plants and animals.
Biosphere
: The total of all areas where living things are found
Temperature and rainfall are the main factors affecting distribution of biomes
Temperature influences rate of metabolism, affecting the phases in the life cycles of organisms
Availability of freshwater is critical to growth and nutrition.
Climograph
: A diagram which shows the relative combination of temperature and precipitation in an area
Shows the stable ecosystems/biomes that arise as a result of temperature an precipitation
Ecological Succession
: The predictable and orderly changes in composition of an ecosystem over time.
Primary succession
: The emergence of an entirely new ecosystem, such as a volcanic island
Gross production increases
Larger plants take root as soil deepens
Productivity plateaus as soil's carrying capacity is reached
Soil builds up, following death of smaller lichens
First colonizers are lichens on rock surfaces
Species diversity increases
More plants take root and provide new niches
More death leads to more soil and nutrient recycling
More soils allows for burrowers, worms, and detritivores
Living organisms change the abiotic environment
Soil
Detritivores and bacteria fix nitrogen and other inorganic nutrients into the soil
Decay accumulates minerals around roots
Produced by detritivores (worms)
Aerated by burrowing animals: more respiration and drainage
Plant roots
Bin the soil, preventing erosion
Support large plants
Uptake, filter and recycle massive amounts of water, preventing flood and drought
Secondary succession
: The replacement of one ecosystem by another following environmental change, such as grassland growing into woodland
Secondary succession is caused by a disturbance to an ecosystem
A wildfire destroys a forrest, leaves behind soil, plants slowly begin to grow on the soil, larger plants being to grow and species begin to diversify creating a new ecosystem